4-Amino-5-cyano-2-anilino-pyrimidine derivatives and their use as inhibitors of cell-cycle kinases

ABSTRACT

Compounds of formula (I) wherein: R 1  is halo, nitro, cyano, hydroxy, amino, carboxy, carbamoyl, mercapto, C 1-6 alkyl, C 2-6 alkenyl or C 2-6 alkynyl; p is 0-4; wherein the values of R 1  may be the same or different; R 2  is sulphamoyl or a group B-E- ; wherein B is optionally substituted as defined within and is selected from C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-8 cycloalkyl, C 1-6 alkyl, phenyl, a heterocyclic group, phenylC 1-6 alkyl or (heterocyclic group)C 1-6 alkyl; E is C(O)—, N(R a )C(O)—, —C(O)N(R a )—, —S(O) r —, —SO 2 N(R a )— or —N(R a )SO 2 —; wherein R a  is hydrogen or C 1-6 alkyl optionally substituted as defined within and r is 1-2; q is 0-2; wherein the values of R 2  may be the same or different; and wherein p+q=1-5; or a pharmaceutically acceptable salt or an in vivo hydrolysable ester thereof are described. Processes for their manufacture and their use as inhibitors of cell cycle kinases, particularly CDK2, CDK4 and/or CDK6 are also described

The invention relates to pyrimidine derivatives, or pharmaceuticallyacceptable salts or in vivo hydrolysable esters thereof, which possesscell-cycle inhibitory activity and are accordingly useful for theiranti-cell-proliferation (such as anti-cancer) activity and are thereforeuseful in methods of treatment of the human or animal body. Theinvention also relates to processes for the manufacture of saidpyrimidine derivatives, to pharmaceutical compositions containing themand to their use in the manufacture of medicaments of use in theproduction of an anti-cell-proliferation effect in a warm-blooded animalsuch as man.

A family of intracellular proteins called cyclins play a central role inthe cell cycle. The synthesis and degradation of cyclins is tightlycontrolled such that their level of expression fluctuates during thecell cycle. Cyclins bind to cyclin-dependent serine/threonine kinases(CDKs) and this association is essential for CDK (such as CDK1, CDK2,CDK4 and/or CDK6) activity within the cell. Although the precise detailsof how each of these factors combine to regulate CDK activity is poorlyunderstood, the balance between the two dictates whether or not the cellwill progress through the cell cycle.

The recent convergence of oncogene and tumour suppressor gene researchhas identified regulation of entry into the cell cycle as a key controlpoint of mitogenesis in tumours. Moreover, CDKs appear to be downstreamof a number of oncogene signalling pathways. Disregulation of CDKactivity by upregulation of cyclins and/or deletion of endogenousinhibitors appears to be an important axis between mitogenic signallingpathways and proliferation of tumour cells.

Accordingly it has been recognised that an inhibitor of cell cyclekinases, particularly inhibitors of CDK2, CDK4 and/or CDK6 (whichoperate at the S-phase, G1-S and G1-S phase respectively) should be ofvalue as a selective inhibitor of cell proliferation, such as growth ofmammalian cancer cells.

The present invention is based on the discovery that certain pyrimidinecompounds surprisingly inhibit the effects of cell cycle kinases showingselectivity for CDK2, CDK4 and CDK6, and thus possessanti-cell-proliferation properties. Such properties are expected to beof value in the treatment of disease states associated with aberrantcell cycles and cell proliferation such as cancers (solid tumours andleukemias), fibroproliferative and differentiative disorders, psoriasis,rheumatoid arthritis, Kaposi's sarcoma, haemangioma, acute and chronicnephropathies, atheroma, atherosclerosis, arterial restenosis,autoimmune diseases, acute and chronic inflammation, bone diseases andocular diseases with retinal vessel proliferation.

Accordingly, the present invention provides a compound of formula (I):

wherein:

R¹ is halo, nitro, cyano, hydroxy, amino, carboxy, carbamoyl, mercapto,C₁₋₆alkyl, C₂₋₆alkenyl or C₂₋₆alkynyl;

p is 0-4; wherein the values of R¹ may be the same or different;

R² is sulphamoyl or a group B-E-; wherein

B is selected from C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₃₋₈cycloalkyl,C₃₋₈cycloalkylC₁₋₆alkyl, phenyl, a heterocyclic group, phenylC₁₋₆alkylor (heterocyclic group)C₁₋₆alkyl; wherein said C₁₋₆alkyl, C₂₋₆alkenyl,C₂₋₆alkynyl, C₃₋₈cycloalkyl, C₃₋₈cycloalkylC₁₋₆alkyl, phenyl,heterocyclic group, phenylC₁₋₆alkyl or (heterocyclic group)C₁₋₆alkyl areoptionally substituted on carbon by one or more D; and wherein if saidheterocyclic group contains an —NH— moiety that nitrogen may beoptionally substituted by a group selected from G;

E is —C(O)—, —N(R^(a))C(O)—, —C(O)N(R^(a))—, —S(O)_(r)—, —SO₂N(R^(a))—or —N(R^(a))SO₂—; wherein R^(a) is hydrogen or C₁₋₆alkyl optionallysubstituted by one or more D and r is 1-2;

D is independently selected from halo, nitro, cyano, hydroxy,trifluoromethyl, trifluoromethoxy, amino, carboxy, carbamoyl, mercapto,sulphamoyl, C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy,C₁₋₆alkanoyl, C₁₋₆alkanoyloxy, N-(C₁₋₆alkyl)amino,N,N-(C₁₋₆alkyl)₂amino, C₁₋₆alkanoylamino, N-(C₁₋₆alkyl)carbamoyl,N,N-(C₁₋₆alkyl)₂carbamoyl, C₁₋₆alkylS(O)₂ wherein a is 0 to 2,C₁₋₆alkoxycarbonyl, N-(C₁₋₆alkyl)sulphamoyl andN,N-(C₁₋₆alkyl)₂sulphamoyl;

G is selected from C₁₋₄alkyl, C₁₋₄alkanoyl, C₁₋₄alkylsulphonyl,C₁₋₄alkoxycarbonyl, carbamoyl, N-(C₁₋₄alkyl)carbamoyl,N,N-(C₁₋₄alkyl)carbamoyl, benzyl, benzyloxycarbonyl, benzoyl andphenylsulphonyl; and

q is 0-2; wherein the values of R² maybe the same or different; andwherein p+q=1-5;

or a pharmaceutically acceptable salt or an in vivo hydrolysable esterthereof

In another aspect of the invention, there is provided a compound offormula (I) or a pharmaceutically acceptable salt or an in vivohydrolysable ester thereof with the proviso that that compound is not2-(2,4-dimethylanilino)-4-amino-5-cyanopyrimidine.

In this specification the term “alkyl” includes both straight andbranched chain alkyl groups but references to individual alkyl groupssuch as “propyl” are specific for the straight chain version only. Forexample, “C₁₋₆alkyl” includes C₁₋₄alkyl, C₁₋₃alkyl, propyl, isopropyland t-butyl. However, references to individual alkyl groups such as‘propyl’ are specific for the straight chained version only andreferences to individual branched chain alkyl groups such as ‘isopropyl’are specific for the branched chain version only. A similar conventionapplies to other radicals, for example “phenylC₁₋₆alkyl” includesphenylC₁₋₄alkyl, benzyl, 1-phenylethyl and 2-phenylethyl. The term“halo” refers to fluoro, chloro, bromo and iodo.

Where optional substituents are chosen from “one or more” groups it isto be understood that this definition includes all substituents beingchosen from one of the specified groups or the substituents being chosenfrom two or more of the specified groups.

A “heterocyclic group” is a saturated, partially saturated orunsaturated, mono or bicyclic ring containing 4-12 atoms of which atleast one atom is chosen from nitrogen, sulphur or oxygen, which may,unless otherwise specified, be carbon or nitrogen linkled, wherein a—CH₂— group can optionally be replaced by a —C(O)—, a ring nitrogen atommay optionally bear a C₁₋₆alkyl group and form a quaternary compound ora ring nitrogen and/or sulphur atom may be optionally oxidised to formthe N-oxide and or the S-oxides. Examples and suitable values of theterm “heterocyclic group” are morpholino, piperidyl, pyridyl, pyranyl,pyrrolyl, isothiazolyl, indolyl, quinolyl, thienyl, 1,3-benzodioxolyl,thiadiazolyl, piperazinyl, thiazolidinyl, pyrrolidinyl, thiomorpholino,pyrrolinyl, homopiperazinyl, 3,5-dioxapiperidinyl, tetrahydropyranyl,imidazolyl, pyrimidyl, pyrazinyl, pyridazinyl, isoxazolyl,N-methylpyrrolyl, 4-pyridone, 1-isoquinolone, 2-pyrrolidone,4-thiazolidone, pyridine-N-oxide and quinoline-N-oxide. Preferably a“heterocyclic group” is a saturated, partially saturated or unsaturated,mono or bicyclic ring containing 5 or 6 atoms of which at least one atomis chosen from nitrogen, sulphur or oxygen, it may, unless otherwisespecified, be carbon or nitrogen linked, a —CH₂— group can optionally bereplaced by a —C(O)— and a ring sulphur atom may be optionally oxidisedto form the S-oxides. More preferably a “heterocyclic group” istetrahydrofuryl, pyridyl, pyrrolidinonyl, morpholino, imidazolyl,piperidinyl or pyrrolidinyl.

An example of “C₁₋₆alkanoyloxy” is acetoxy. Examples of“C₁₋₆alkoxycarbonyl” include C₁₋₄alkoxycarbonyl, methoxycarbonyl,ethoxycarbonyl, n- and t-butoxycarbonyl. Examples of “C₁₋₆alkoxy”include methoxy, ethoxy and propoxy. Examples of “C₁₋₆alkanoylamino”include formamido, acetamido and propionylamino. Examples of“C₁₋₆alkylS(O)_(a) wherein a is 0 to 2” include C₁₋₄alkylsulphonyl,methylthio, ethylthio, methylsulphinyl, ethylsulphinyl, mesyl andethylsulphonyl. Examples of “C₁₋₆alkylS(O)_(r) wherein r is 1 to 2”include methylsulphinyl, ethylsulphinyl, mesyl and ethylsulphonyl.Examples of “C₁₋₆alkanoyl” include C₁₋₄alkanoyl, propionyl and acetyl.Examples of “N-C₁₋₆alkylamino” include methylamino and ethylamino.Examples of “N,N-(C₁₋₆alkyl)₂amino” include di-N-methylamino,di-(N-ethyl)amino and N-ethyl-N-methylamino. Examples of “C₂₋₆alkenyl”are vinyl, allyl and 1-propenyl Examples of “C₂₋₆alkynyl” are ethynyl,1-propynyl and 2-propynyl. Examples of “N-(C₁₋₆alkyl)sulphamoyl” areN-(methyl)sulphamoyl and N-(ethyl)sulphamoyl. Examples of“N-(C₁₋₆alkyl)₂sulphamoyl” are N,N-(dimethyl)sulphamoyl andN-(methyl)-N-(ethyl)sulphamoyl. Examples of “N-(C₁₋₆alkyl)carbamoyl” areN-(C₁₋₄alkyl)carbamoyl, methylaminocarbonyl and ethylaminocarbonyl.Examples of “N,N-(C₁₋₆alkyl)₂carbamoyl” are N,N-(C₁₋₄alkyl)₂carbamoyl,dimethylaminocarbonyl and methylethylaminocarbonyl. Examples of“C₃₋₈cycloalkyl” are cyclopropyl, cyclobutyl, cyclopropyl andcyclohexyl. Examples of “(heterocyclic group)C₁₋₆alkyl” includepyridylmethyl, 3-morpholinopropyl and 2-pyrimid-2-ylethyl. Examples of“C₃₋₈cycloalkylC₁₋₆alkyl” are cyclopropylethyl, cyclobutylmethyl,2-cyclopropylpropyl and cyclohexylethyl.

A suitable pharmaceutically acceptable salt of a compound of theinvention is, for example, an acid-addition salt of a compound of theinvention which is sufficiently basic, for example, an acid-additionsalt with, for example, an inorganic or organic acid, for examplehydrochloric, hydrobromic, sulphuric, phosphoric, trifluoroacetic,citric or maleic acid. In addition a suitable pharmaceuticallyacceptable salt of a compound of the invention which is sufficientlyacidic is an alkali metal salt, for example a sodium or potassium salt,an alkaline earth metal salt, for example a calcium or magnesium salt,an ammonium salt or a salt with an organic base which affords aphysiologically-acceptable cation, for example a salt with methylamine,dimethylamine, trimethylamine, piperidine, morpholine ortris-(2-hydroxyethyl)amine.

The compounds of the formula (I) may be administered in the form of apro-drug which is broken down in the human or animal body to give acompound of the formula (I). Examples of pro-drugs include in vivohydrolysable esters of a compound of the formula (I).

An in vivo hydrolysable ester of a compound of the formula (I)containing carboxy or hydroxy group is, for example, a pharmaceuticallyacceptable ester which is hydrolysed in the human or animal body toproduce the parent acid or alcohol. Suitable pharmaceutically acceptableesters for carboxy include C₁₋₆alkoxymethyl esters for examplemethoxymethyl, C₁₋₆alkanoyloxymethyl esters for examplepivaloyloxymethyl, phthalidyl esters,C₃₋₈cycloalkoxycarbonyloxyC₁₋₆alkyl esters for example1-cyclohexylcarbonyloxyethyl; 1,3-dioxolen-2-onylmethyl esters forexample 5-methyl-1,3-dioxolen-2-onylmethyl; andC₁₋₆alkoxycarbonyloxyethyl esters for example 1-methoxycarbonyloxyethyland may be formed at any carboxy group in the compounds of thisinvention.

An in vivo hydrolysable ester of a compound of the formula (I)containing a hydroxy group includes inorganic esters such as phosphateesters and α-acyloxyalkyl ethers and related compounds which as a resultof the in vivo hydrolysis of the ester breakdown to give the parenthydroxy group. Examples of α-acyloxyalkyl ethers include acetoxymethoxyand 2,2-dimethylpropionyloxy-methoxy. A selection of in vivohydrolysable ester forming groups for hydroxy include alkanoyl, benzoyl,phenylacetyl and substituted benzoyl and phenylacetyl, alkoxycarbonyl(to give alkyl carbonate esters), dialkylcarbamoyl andN-(dialkylaminoethyl)-N-alkylcarbamoyl (to give carbamates),dialkylaminoacetyl and carboxyacetyl. Examples of substituents onbenzoyl include morpholino and piperazino linked from a ring nitrogenatom via a methylene group to the 3- or 4-position of the benzoyl ring.

Some compounds of the formula (I) may have chiral centres and/orgeometric isomeric centres (E- and Z-isomers), and it is to beunderstood that the invention encompasses all such optical,diastereoisomers and geometric isomers that possess CDK inhibitoryactivity.

The invention relates to any and all tautomeric forms of the compoundsof the formula (I) that possess CDK inhibitory activity.

It is also to be understood that certain compounds of the formula (I)can exist in solvated as well as unsolvated forms such as, for example,hydrated forms. It is to be understood that the invention encompassesall such solvated forms which possess CDK inhibitory activity.

Preferred values of R¹, R², p and q are as follows. Such values may beused where appropriate with any of the definitions, claims orembodiments defined hereinbefore or hereinafter.

Preferably R¹ is halo or C₁₋₂alkyl.

More preferably R¹ is fluoro, chloro or methyl.

Particularly R¹ is fluoro or chloro.

More particularly R¹ is chloro.

Preferably R¹ is meta or para to the amino group of the aniline informula (I).

More preferably R¹ is meta to the amino group of the aniline in formula(I).

Preferably p is 0-2; wherein the values of R¹ may be the same ordifferent.

More preferably p is 0 or 1.

In one aspect of the invention preferably p is 0.

In another aspect of the invention preferably p is 1.

In a further aspect of the invention preferably p is 2; wherein thevalues of R¹ may be the same or different.

Preferably R² is sulphamoyl or a group B-E-; wherein

B is selected from C₁₋₆alkyl, C₂₋₆alkenyl, C₃₋₈cycloalkyl,C₃₋₈cycloalkylC₁₋₆alkyl, phenylC₁₋₆alkyl or (heterocyclicgroup)C₁₋₆alkyl; wherein said C₁₋₆alkyl, C₂₋₆alkenyl, C₃₋₈cycloalkyl,C₃₋₈cycloalkylC₁₋₆alkyl, phenylC₁₋₆alkyl or (heterocyclicgroup)C₁₋₆alkyl are optionally substituted on carbon by one or more D;and wherein if said heterocyclic group contains an —NH— moiety thatnitrogen may be optionally substituted by a group selected from G;

E is —N(R^(a))SO₂—; wherein R^(a) is hydrogen;

D is independently selected from halo, hydroxy, C₁₋₆alkoxy orN-(C₁₋₆alkyl)amino, N,N-(C₁₋₆alkyl)₂amino; and

G is C₁₋₄alkyl.

More preferably R² is sulphamoyl or a group B-E-; wherein

B is optionally substituted by D and is selected from ethyl, propyl,pentyl, allyl, cyclopropyl, cyclobutyl, cyclopropylmethyl, benzyl,phenethyl, tetrahydrofurylmethyl, pyridylethyl, pyrrolidinonylpropyl,morpholinopropyl, imidazolylpropyl, piperidinylethyl, pyrrolidinylethyl(optionally substituted on the ring nitrogen by methyl),

E is —NHSO₂—;

D is independently selected from fluoro, hydroxy, methoxy, ethoxy,isopropoxy, isopropylamino and dimethylamino.

Particularly R² is selected from sulphamoyl,N-(cyclopropylmethyl)sulphamoyl, N-(tetrahydrofur-2-ylmethyl)sulphamoyl,N-(2-methoxyethyl)sulphamoyl, N-(2-pyrid-2-ylethyl)sulphamoyl,N-(2-piperidin-1-ylethyl)sulphamoyl,N-[2-(1-methylpyrrolidin-2-yl)ethyl]sulphamoyl,N-(2-isopropylaminoethyl)sulphamoyl, N-(2,2,2-trifluoroethyl)sulphamoyl,N-(3-methoxypropyl)sulphamoyl, N-(3-ethoxypropyl)sulphamoyl,N-(3-isopropoxypropyl)sulphamoyl, N-(3-dimethylaminopropyl)sulphamoyl,N-[3-(2-oxopyrrolidin-1-yl)propyl]sulphamoyl,N-(3-morpholinopropyl)sulphamoyl, N-(3-imidazol-1-ylpropyl)sulphamoyl,N-(3-isopropylaminopropyl)sulphamoyl, N-(propyl)sulphamoyl,N-(pentyl)sulphamoyl, N-(allyl)sulphamoyl, N-(cyclopropyl)sulphamoyl,N-(cyclobutyl)sulphamoyl, N-(3-methoxybenzyl)sulphamoyl,N-(4-fluorobenzyl)sulphamoyl, N-(phenethyl)sulphamoyl,N-(4-hydroxyphenethyl)sulphamoyl and N-(4-methoxyphenethyl)sulphamoyl.

In another aspect of the invention, preferably R² is sulphamoyl or agroup B-E-; wherein

B is selected from C₁₋₆alkyl, C₁₋₆alkenyl, C₃₋₈cycloalkyl,C₃₋₈cycloalkylC₁₋₆alkyl, phenylC₁₋₆alkyl or (heterocyclicgroup)C₁₋₆alkyl; wherein said C₁₋₆alkyl, C₂₋₆alkenyl, C₃₋₈cycloalkyl,C₃₋₈cycloakylC₁₋₆alkyl, phenylC₁₋₆alkyl or (heterocyclic group)C₁₋₆alkylare optionally substituted on carbon by one or more D; and wherein ifsaid heterocyclic group contains an —NH— moiety that nitrogen may beoptionally substituted by a group selected from G;

E is —N(R^(a))SO₂— or —N(R^(a))C(O)—; wherein R^(a) is hydrogen;

D is independently selected from halo, hydroxy, C₁₋₆alkoxy orN-(C₁₋₆alkyl)amino, N,N-(C₁₋₆alkyl)₂amino; and

G is C₁₋₄alkyl.

In another aspect of the invention, more preferably R² is sulphamoyl ora group B-E-; wherein

B is optionally substituted by D and is selected from ethyl, propyl,pentyl, 2,2-dimethylpropyl, allyl, cyclopropyl, cyclobutyl,cyclopropylmethyl, benzyl, phenethyl, tetrahydrofurylmethyl,pyridylethyl, pyrrolidinonylpropyl, morpholinopropyl, imidazolylpropyl,piperidinylethyl, pyrrolidinylethyl (optionally substituted on the ringnitrogen by methyl),

E is —NHSO₂— or —N(R^(a))C(O)—;

D is independently selected from fluoro, hydroxy, methoxy, ethoxy,isopropoxy, isopropylamino and dimethylamino.

In another aspect of the invention, particularly R² is selected fromsulphamoyl, N-(cyclopropylmethyl)sulphamoyl,N-(tetrahydrofur-2-ylmethyl)sulphamoyl, N-(2-methoxyethyl)sulphamoyl,N-(2-pyrid-2-ylethyl)sulphamoyl, N-(2-piperidin-1-ylethyl)sulphamoyl,N-[2-(1-methylpyrrolidin-2-yl)ethyl]sulphamoyl,N-(2-isopropylaminoethyl)sulphamoyl, N-(9,2,2-trifluoroethyl)sulphamoyl,N-(2-dimethylaminoethyl)sulphamoyl, N-(3-methoxypropyl)sulphamoyl,N-(3-ethoxypropyl)sulphamoyl, N-(3-isopropoxypropyl)sulphamoyl,N-(3-dimethylaminopropyl)sulphamoyl,N-[3-(2-oxopyrrolidin-1-yl)propyl]sulphamoyl,N-(3-morpholinopropyl)sulphamoyl, N-(3-imidazol-1-ylpropyl)sulphamoyl,N-(3-isopropylaminopropyl)sulphamoyl, N-(propyl)sulphamoyl,N-(3-hydroxy-2,2-dimethylpropyl)sulphamoyl, N-(pentyl)sulphamoyl,N-(allyl)sulphamoyl, N-(cyclopropyl)sulphamoyl,N-(cyclobutyl)sulphamoyl, N-(3-methoxybenzyl)sulphamoyl,N-(4-fluorobenzyl)sulphamoyl, N-(phenethyl)sulphamoyl,N-(4-hydroxyphenethyl)sulphamoyl, N-(4-methoxyphenethyl)sulphamoyl andN-(3-imidazol-1-ylpropyl)carbamoyl.

Preferably R² is meta or para to the amino group of the aniline informula (I).

More preferably R² is para to the amino group of the aniline in formula(I).

Preferably E is —NHSO₂—.

In another aspect of the invention, preferably E is —NHSO₂— or—N(R^(a))C(O)—.

Preferably q is 0 or 1.

In one aspect of the invention preferably q is 0.

In another aspect of the invention preferably q is 1.

In a further aspect of the invention preferably q is 2; wherein thevalues of R² may be the same or different.

Preferably p+q=1 or 2.

More preferably p+q=1.

Therefore in one aspect of the invention, there is provided a compoundof formula (I) as depicted above wherein:

R¹ is halo or C₁₋₂alkyl;

p is 0-2; wherein the values of R¹ may be the same or different;

R² is sulphamoyl or a group B-E-; wherein

B is selected from C₁₋₆alkyl, C₂₋₆alkenyl, C₃₋₈cycloalkyl,C₃₋₈cycloalkylC₁₋₆alkyl, phenylC₁₋₆alkyl or (heterocyclicgroup)C₁₋₆alkyl; wherein said C₁₋₆alkyl, C₂₋₆alkenyl, C₃₋₈cycloalkyl,C₃₋₈cycloalkylC₁₋₆alkyl, phenylC₁₋₆alkyl or (heterocyclicgroup)C₁₋₆alkyl are optionally substituted on carbon by one or more D;and wherein if said heterocyclic group contains an —NH— moiety thatnitrogen may be optionally substituted by a group selected from G;

E is —N(R^(a))SO₂—; wherein R¹ is hydrogen;

D is independently selected from halo, hydroxy, C₁₋₆alkoxy orN-(C₁₋₆alkyl)amino, N,N-(C₁₋₆alkyl)₂amino;

G is C₁₋₄alkyl; and

q is 0 or 1; and p+q=1 or 2;

or a pharmaceutically acceptable salt or an in vivo hydrolysable esterthereof.

Therefore in a further aspect of the invention, there is provided acompound of formula (I) as depicted above wherein:

R¹ is fluoro, chloro or methyl;

p is 0 or 1;

R² is sulphamoyl or a group B-E-; wherein

B is optionally substituted by D and is selected from ethyl, propyl,pentyl, allyl, cyclopropyl, cyclobutyl, cyclopropylmethyl, benzyl,phenethyl, tetrahydrofurylmethyl, pyridylethyl, pyrrolidinonylpropyl,morpholinopropyl, imidazolylpropyl, piperidinylethyl, pyrrolidinylethyl(optionally substituted on the ring nitrogen by methyl),

E is —NHSO₂—;

D is independently selected from fluoro, hydroxy, methoxy, ethoxy,isopropoxy, isopropylamino and dimethylamino; and

q is 0 or 1; and p+q=1 or 2;

or a pharmaceutically acceptable salt or an in vivo hydrolysable esterthereof.

Therefore in an additional aspect of the invention, there is provided acompound of formula (I) as depicted above wherein:

p is 0;

R² is selected from sulphamoyl, N-(cyclopropylmethyl)sulphamoyl,N-(tetrahydrofur-2-ylmethyl)sulphamoyl, N-(2-methoxyethyl)sulphamoyl,N-(2-pyrid-2-ylethyl)sulphamoyl, N-(2-piperidin-1-ylethyl)sulphamoyl,N-[2-(1-methylpyrrolidin-2-yl)ethyl]sulphamoyl,N-(2-isopropylaminoethyl)sulphamoyl, N-(2,2,2-trifluoroethyl)sulphamoyl,N-(3-methoxypropyl)sulphamoyl, N-(3-ethoxypropyl)sulphamoyl,N-(3-isopropoxypropyl)sulphamoyl, N-(3-dimethylaminopropyl)sulphamoyl,N-[3-(2-oxopyrrolidin-1-yl)propyl]sulphamoyl,N-(3-morpholinopropyl)sulphamoyl, N-(3-imidazol-1-ylpropyl)sulphamoyl,N-(3-isopropylaminopropyl)sulphamoyl, N-(propyl)sulphamoyl,N-(pentyl)sulphamoyl, N-(allyl)sulphamoyl, N-(cyclopropyl)sulphamoyl,N-(cyclobutyl)sulphamoyl, N-(3-methoxybenzyl)sulphamoyl,N-(4-fluorobenzyl)sulphamoyl, N-(phenethyl)sulphamoyl,N-(4-hydroxyphenethyl)sulphamoyl and N-(4-methoxyphenethyl)sulphamoyl;and

q is 1;

or a pharmaceutically acceptable salt or an in vivo hydrolysable esterthereof.

In another aspect of the invention, preferred compounds of the inventionare any one of Examples 1-27 or a pharmaceutically acceptable salt or anin vivo hydrolysable esters thereof.

In another aspect of the invention, preferred compounds of the inventionare any one of Examples 1-31 or a pharmaceutically acceptable salt or anin vivo hydrolysable esters thereof.

In a further aspect of the invention, preferred compounds of formula (I)are:

-   4-amino-5-cyano-2-{4-[N-(2-methoxyethyl)sulphamoyl]anilino}pyrimidine;-   4-amino-5-cyano-2-{4-[N-(tetrahydrofur-2-ylmethyl)sulphamoyl]anilino}pyrimidine;-   4-amino-5-cyano-2-{4-[N-(4-fluorobenzyl)sulphamoyl]anilino}pyrimidine;-   4-amino-5-cyano-2-{4-[N-(3-methoxypropyl)sulphamoyl]anilino}pyrimidine;-   4-amino-5-cyano-2-{4-[N-(cyclopropyl)sulphamoyl]anilino}pyrimidine;-   4-amino-5-cyano-2-[4-(N-allylsulphamoyl)anilino]pyrimidine;-   4-amino-5-cyano-2-[4-(N-propylsulphamoyl)anilino]pyrimidine;-   4-amino-5-cyano-2-{4-[N-(2-isopropylaminoethyl)sulphamoyl]anilino}pyrimidine;-   4-amino-5-cyano-2-{4-[N-(3-isopropylaminopropyl)sulphamoyl]anilino}pyrimidine;    and-   4-amino-5-cyano-2-{4-[N-(2-piperidinoethyl)sulphamoyl]anilino}pyrimidine;    or a pharmaceutically acceptable salt or an in vivo hydrolysable    ester thereof.

Preferred aspects of the invention are those which relate to thecompound of formula (I) or a pharmaceutically acceptable salt thereof.

Another aspect of the present invention provides a process for preparinga compound of formula (I) or a pharmaceutically acceptable salt or an invivo hydrolysable ester thereof which process (wherein R¹, R², p and qare, unless otherwise specified, as defined in formula (I)) comprisesof:

-   a) reaction of a pyrimidine of formula (II):-   wherein L is a displaceable group; with an aniline of formula (III):-   b) reacting a pyrimidine of formula (IV):-   wherein L is a displaceable group; with ammonia; or-   c) reacting a compound of formula (V):-   with a compound of formula (VI):-   wherein X is O or S; R³ is C₁₋₆alkyl;-   d) reacting a compound of formula (V) with a compound of formula    (VII):-   e) where R² is sulphamoyl or a group B-E- and E is —NHSO₂—; reacting    a pyrimidine of formula (VIII):-   wherein X is a displaceable group; with an amine of formula (IX):    B—NH₂  (IX)-   and thereafter if necessary:-   i) converting a compound of the formula (I) into another compound of    the formula (I);-   ii) removing any protecting groups;-   iii) forming a pharmaceutically acceptable salt or in vivo    hydrolysable ester.

L is a displaceable group, suitable values for L are for example, ahalogeno or sulphonyloxy group, for example a chloro, bromo,methanesulphonyloxy or toluene-4-sulphonyloxy group.

X is a displaceable group, suitable values for L are for example, ahalogeno group, for example a fluoro, chloro or bromo group. PreferablyX is fluoro.

Specific reaction conditions for the above reactions are as follows.

-   a) and b) Pyrimidines of formula (II) and anilines of formula (III)    and pyrimidines of formula (IV) and ammonia may be reacted together:-   i) in the presence of a suitable solvent for example a ketone such    as acetone or an alcohol such as ethanol or butanol or an aromatic    hydrocarbon such as toluene or N-methyl pyrrolidine, optionally in    the presence of a suitable acid for example an inorganic acid such    as hydrochloric acid or sulphuric acid, or an organic acid such as    acetic acid or formic acid (or a suitable Lewis acid) and at a    temperature in the range of 0° C. to reflux, preferably reflux; or-   ii) under standard Buchwald conditions (for example see J. Am. Chem.    Soc., 118, 7215; J. Am. Chem. Soc., 119, 8451; J. Org. Chem., 62,    1568 and 6066) for example in the presence of palladium acetate, in    a suitable solvent for example an aromatic solvent such as toluene,    benzene or xylene, with a suitable base for example an inorganic    base such as caesium carbonate or an organic base such as    potassium-t-butoxide, in the presence of a suitable ligand such as    2,2′-bis(diphenylphosphino)-1,1′-binaphthyl and at a temperature in    the range of 25 to 80° C.

Pyrimidines of the formula (II) and (IV) and anilines of formula (III)are commercially available compounds, or they are known in theliterature, or they are prepared by standard processes known in the art.

-   c) and d) Compounds of formula (V) and compounds of formula (VI) or    formula (VII) are reacted together in a suitable solvent such as    N-methylpyrrolidinone or butanol at a temperature in the range of    100-200° C., preferably in the range of 150-170° C. The reaction is    preferably conducted in the presence of a suitable base such as, for    example, sodium methoxide or potassium carbonate.

Compounds of formula (V) and (VI) are commercially available compounds,or they are known in the literature, or they are prepared by standardprocesses known in the art.

-   e) Compounds of formula (VIII) and compounds of formula (IX) may be    reacted together in the presence of a base for example an inorganic    base such as caesium carbonate in the presence of an inert solvent    such as toluene or tetrahydrofuran, or in the presence of an organic    base such as excess (IX) and at a temperature in the range of 25 to    80° C.

Compounds of formula (VIII) wherein X is fluoro may be preparedaccording to the following scheme:

Compounds of formula (VIIIa) and (IX) are commercially availablecompounds, or they are known in the literature, or they are prepared bystandard processes known in the art.

It will be appreciated that certain of the various ring substituents inthe compounds of the present invention may be introduced by standardaromatic substitution reactions or generated by conventional functionalgroup modifications either prior to or immediately following theprocesses mentioned above, and as such are included in the processaspect of the invention. Such reactions and modifications include, forexample, introduction of a substituent by means of an aromaticsubstitution reaction, reduction of substituents, alkylation ofsubstituents and oxidation of substituents. The reagents and reactionconditions for such procedures are well known in the chemical art.Particular examples of aromatic substitution reactions include theintroduction of a nitro group using concentrated nitric acid, theintroduction of an acyl group using, for example, an acyl halide andLewis acid (such as aluminium trichloride) under Friedel Craftsconditions; the introduction of an alkyl group using an alkyl halide andLewis acid (such as aluminium trichloride) under Friedel Craftsconditions; and the introduction of a halogeno group. Particularexamples of modifications include the reduction of a nitro group to anamino group by for example, catalytic hydrogenation with a nickelcatalyst or treatment with iron in the presence of hydrochloric acidwith heating; oxidation of alkylthio to alkylsulphinyl oralkylsulphonyl.

It will also be appreciated that in some of the reactions mentionedherein it may be necessary/desirable to protect any sensitive groups inthe compounds. The instances where protection is necessary or desirableand suitable methods for protection are known to those skilled in theart. Conventional protecting groups may be used in accordance withstandard practice (for illustration see T. W. Green, Protective Groupsin Organic Synthesis, John Wiley and Sons, 1991). Thus, if reactantsinclude groups such as amino, carboxy or hydroxy it may be desirable toprotect the group in some of the reactions mentioned herein.

A suitable protecting group for an amino or alkylamino group is, forexample, an acyl group, for example an alkanoyl group such as acetyl, analkoxycarbonyl group, for example a methoxycarbonyl, ethoxycarbonyl ort-butoxycarbonyl group, an arylmethoxycarbonyl group, for examplebenzyloxycarbonyl, or an aroyl group, for example benzoyl. Thedeprotection conditions for the above protecting groups necessarily varywith the choice of protecting group. Thus, for example, an acyl groupsuch as an alkanoyl or alkoxycarbonyl group or an aroyl group may beremoved for example, by hydrolysis with a suitable base such as analkali metal hydroxide, for example lithium or sodium hydroxide.Alternatively an acyl group such as a t-butoxycarbonyl group may beremoved, for example, by treatment with a suitable acid as hydrochloric,sulphuric or phosphoric acid or trifluoroacetic acid and anarylmethoxycarbonyl group such as a benzyloxycarbonyl group may beremoved, for example, by hydrogenation over a catalyst such aspalladium-on-carbon, or by treatment with a Lewis acid for example borontris(trifluoroacetate). A suitable alternative protecting group for aprimary amino group is, for example, a phthaloyl group which may beremoved by treatment with an alkylamine, for exampledimethylaminopropylamine, or with hydrazine.

A suitable protecting group for a hydroxy group is, for example, an acylgroup, for example an alkanoyl group such as acetyl, an aroyl group, forexample benzoyl, or an arylmethyl group, for example benzyl. Thedeprotection conditions for the above protecting groups will necessarilyvary with the choice of protecting group. Thus, for example, an acylgroup such as an alkanoyl or an aroyl group may be removed, for example,by hydrolysis with a suitable base such as an alkali metal hydroxide,for example lithium or sodium hydroxide. Alternatively an arylmethylgroup such as a benzyl group may be removed, for example, byhydrogenation over a catalyst such as palladium-on-carbon.

A suitable protecting group for a carboxy group is, for example, anesterifying group, for example a methyl or an ethyl group which may beremoved, for example, by hydrolysis with a base such as sodiumhydroxide, or for example a t-butyl group which may be removed, forexample, by treatment with an acid, for example an organic acid such astrifluoroacetic acid, or for example a benzyl group which may beremoved, for example, by hydrogenation over a catalyst such aspalladium-on-carbon.

The protecting groups may be removed at any convenient stage in thesynthesis using conventional techniques well known in the chemical art.

As stated hereinbefore the compounds defined in the present inventionpossesses anti-cell-proliferation activity such as anti-cancer activitywhich is believed to arise from the CDK inhibitory activity of thecompound. These properties may be assessed, for example, using theprocedure set out below:

Assay

The following abbreviations have been used:

-   HEPES is N-[2-Hydroxyethyl]piperazine-N′-[2-ethanesulfonic acid]-   DTT is Dithiothretiol-   PMSF is Phenylmethylsulfonyl fluoride

The compounds were tested in an in vitro kinase assay in 96 well formatusing Scintillation Proximity Assay (SPA—obtained from Amersham) formeasuring incorporation of [γ-33-P]-Adenosine Triphosphate into a testsubstrate (GST-Retinoblastoma protein; GST-Rb). In each well was placedthe compound to be tested (diluted in DMSO and water to correctconcentrations) and in control wells either roscovitine as an inhibitorcontrol or DMSO as a positive control.

Approximately 0.2 μl of CDK2/Cyclin E partially-purified enzyme (amountdependent on enzyme activity) diluted in 25 μl incubation buffer wasadded to each well then 20 μl of GST-Rb/ATP/ATP33 mixture (containing0.5 μg GST-Rb and 0.2 μM ATP and 0.14 μCi [γ-33-P]-AdenosineTriphosphate in incubation buffer), and the resulting mixture shakengently, then incubated at room temperature for 60 minutes.

To each well was then added 150 μL stop solution containing (0.8 mg/wellof Protein A-PVT SPA bead (Amersham)), 20 pM/well of Anti-GlutathioneTransferase, Rabbit IgG (obtained from Molecular Probes), 61 mM EDTA and50 mM HEPES pH 7.5 containing 0.05% sodium azide.

The plates were sealed with Topseal-S plate sealers, left for two hoursthen spun at 2500 rpm, 1124×g., for 5 minutes. The plates were read on aTopcount for 30 seconds per well.

The incubation buffer used to dilute the enzyme and substrate mixescontained 50 mM HEPES pH7.5, 10 mM MnCl₂, 1 mM DTT, 100 μM Sodiumvanadate, 100 μM NaF, 10 mM Sodium Glycerophosphate, BSA (1 mg/mlfinal).

Test Substrate

In this assay only part of the retinoblastoma protein (Science 1987 Mar.13;235(4794):1394-1399; Lee W. H., Bookstein R., Hong F., Young L. J.,Shew J. Y., Lee E. Y.) was used, fused to a GST tag. PCR ofretinoblastoma gene encoding amino acids 379-928 (obtained fromretinoblastoma plasmid ATCC pLRbRNL) was performed, and the sequencecloned into pGEX 2T fusion vector (Smith D. B. and Johnson, K. S. Gene67, 31 (1988); which contained a tac promoter for inducible expression,internal I^(q) gene for use in any E.Coli host, and a coding region forthrombin cleavage—obtained from Pharmacia Biotech) which was used toamplify amino acids 792-928. This sequence was again cloned into pGEX2T.

The retinoblastoma 792-928 sequence so obtained was expressed in E.Coli(BL21 (DE3) pLysS cells) using standard inducible expression techniques,and purified as follows.

E.coli paste was resuspended in 10 ml/g of NETN buffer (50 mM Tris pH7.5, 120 mM NaCl, 1 mM EDTA, 0.5% v/v NP-40, 1 mM PMSF, 1 ug/mlleupeptin, 1 ug/ml aprotinin and 1 ug/ml pepstatin) and sonicated for2×45 seconds per 100 ml homogenate. After centrifugation, thesupernatant was loaded onto a 10 ml glutathione Sepharose column(Pharmacia Biotech, Herts, UK), and washed with NETN buffer. Afterwashing with kinase buffer (50 mM HEPES pH 7.5, 10 mM MgCl2, 1 mM DTT, 1mM PMSF, 1 ug/ml leupeptin, 1 ug/ml aprotinin and 1 ug/ml pepstatin) theprotein was eluted with 50 mM reduced glutathione in kinase buffer.Fractions containing GST-Rb(792-927) were pooled and dialysed overnightagainst kinase buffer. The final product was analysed by Sodium DodecaSulfate (SDS) PAGE (Polyacrylamide gel) using 8-16% Tris-Glycine gels(Novex, San Diego, USA).

CDK2 and Cyclin E

The open reading frames of CDK2 and Cyclin E were isolated by reversetranscriptase-PCR using HeLa cell and activated T cell mRNA as atemplate and cloned into the insect expression vector pVL1393 (obtainedfrom Invitrogen 1995 catalogue number: V1392-20). CDK2 and cyclin E werethen dually expressed [using a standard virus Baculogold co-infectiontechnique] in the insect SF21 cell system (Spodoptera Frugiperda cellsderived from ovarian tissue of the Fall Army Worm—commerciallyavailable).

Example Production of Cyclin E/CDK2

The following Example provides details of the production of CyclinE/CDK2 in SF21 cells (in TC100+10% FBS(TCS)+0.2% Pluronic) having dualinfection MOI 3 for each virus of Cyclin E & CDK2.

SF21 cells grown in a roller bottle culture to 2.33×10⁶ cells/ml wereused to inoculate 10×500 ml roller bottles at 0.2×10E6 cells/ml. Theroller bottles were incubated on a roller rig at 28° C.

After 3 days (72 hrs.) the cells were counted, and the average from 2bottles found to be 1.86×10E6 cells/ml. (99% viable). The cultures werethen infected with the dual viruses at an MOI 3 for each virus.

The viruses were mixed together before addition to the cultures, and thecultures returned to the roller rig 28° C.

After 2 days (48 hrs.) post infection the 5 Liters of culture washarvested. The total cell count at harvest was 1.58×10E6 cells/ml.(99%viable). The cells were spun out at 2500 rpm, 30 mins., 4° C. in HeraeusOmnifuge 2.0 RS in 250 ml. lots. The supernatant was discarded.

Partial Co-purification of Cdk2 and Cyclin E

Sf21 cells were resuspended in lysis buffer (50 mM Tris pH 8.2, 10 nmMgCl₂, 1 mM DTT, 10 mM glycerophosphate, 0.1 mM sodium orthovanadate,0.1 mM NaF, 1 mM PMSF, 1 ug/ml leupeptin and 1 ug/ml aprotinin) andhomogenised for 2 minutes in a 10 ml Dounce homgeniser. Aftercentrifugation, the supernatant was loaded onto a Poros HQ/M 1.4/100anion exchange column (PE Biosystems, Hertford, UK). Cdk2 and Cyclin Ewere coeluted at the beginning of a 0-1M NaCl gradient (run in lysisbuffer minus protease inhibitors) over 20 column volumes. Co-elution waschecked by western blot using both anti-Cdk2 and anti-Cyclin Eantibodies (Santa Cruz Biotechnology, California, US).

By analogy, assays designed to assess inhibition of CDK4 and CDK6 may beconstructed. CDK2 (EMBL Accession No. X62071) may be used together withCyclin A or Cyclin E (see EMBL Accession No. M73812), and furtherdetails for such assays are contained in PCT International PublicationNo. WO99/21845, the relevant Biochemical & Biological Evaluationsections of which are hereby incorporated by reference.

Although the pharmacological properties of the compounds of the formula(I) vary with structural change, in general activity possessed bycompounds of the formula (I) may be demonstrated at IC₅₀ concentrationsor doses in the range 250 μM to 1 nM.

When tested in the above in-vitro assay the CDK2 inhibitory activity ofExample 21 was measured as IC₅₀=0.033 μM and that of Example 23 asIC₅₀=0.017 μM.

The in vivo activity of the compounds of the present invention may beassessed by standard techniques, for example by measuring inhibition ofcell growth and assessing cytotoxicity.

Inhibition of cell growth may be measured by staining cells withSulforhodamine B (SRB), a fluorescent dye that stains proteins andtherefore gives an estimation of amount of protein (i.e. cells) in awell (see Boyd, M. R.(1989) Status of the NCI preclinical antitumourdrug discovery screen. Prin. Prac Oncol 10:1-12). Thus, the followingdetails are provided of measuring inhibition of cell growth:

Cells were plated in appropriate medium in a volume of 100 ml in 96 wellplates; media was Dulbecco's Modified Eagle media for MCF-7, SK-UT-1Band SK-UT-1. The cells were allowed to attach overnight, then inhibitorcompounds were added at various concentrations in a maximumconcentration of 1% DMSO (v/v). A control plate was assayed to give avalue for cells before dosing. Cells were incubated at 37° C.; (5% CO₂)for three days.

At the end of three days TCA was added to the plates to a finalconcentration of 16% (v/v). Plates were then incubated at 4° C. for 1hour, the supernatant removed and the plates washed in tap water. Afterdrying, 100 ml SRB dye (0.4% SRB in 1% acetic acid) was added for 30minutes at 37° C. Excess SRB was removed and the plates washed in 1%acetic acid. The SRB bound to protein was solubilised in 10 mM TrispH7.5 and shaken for 30 minutes at room temperature. The ODs were readat 540 nm, and the concentration of inhibitor causing 50% inhibition ofgrowth was determined from a semi-log plot of inhibitor concentrationversus absorbance. The concentration of compound that reduced theoptical density to below that obtained when the cells were plated at thestart of the experiment gave the value for toxicity.

Typical IC₅₀ values for compounds of the invention when tested in theSRB assay are in the range 1 mM to 1 nM.

According to a further aspect of the invention there is provided apharmaceutical composition which comprises a pyrimidine derivative ofthe formula (I), or a pharmaceutically acceptable salt or in vivohydrolysable ester thereof, as defined hereinbefore in association witha pharmaceutically-acceptable diluent or carrier.

The composition may be in a form suitable for oral administration, forexample as a tablet or capsule, for parenteral injection (includingintravenous, subcutaneous, intramuscular, intravascular or infusion) asa sterile solution, suspension or emulsion, for topical administrationas an ointment or cream or for rectal administration as a suppository.

In general the above compositions may be prepared in a conventionalmanner using conventional excipients.

The compound of formula (I) will norm ally be administered to awarm-blooded animal at a unit dose within the range 5-5000 mg per squaremeter body area of the animal, i.e. approximately 0.1-100 mg/kg, andthis normally provides a therapeutically-effective dose. A unit doseform such as a tablet or capsule will usually contain, for example 1-250mg of active ingredient. Preferably a daily dose in the range of 1-50mg/kg is employed. However the daily dose will necessarily be varieddepending upon the host treated, the particular route of administration,and the severity of the illness being treated. Accordingly the optimumdosage may be determined by the practitioner who is treating anyparticular patient.

According to a further aspect of the present invention there is provideda compound of the formula (I), or a pharmaceutically acceptable salt orin vivo hydrolysable ester thereof, as defined hereinbefore for use in amethod of treatment of the human or animal body by therapy.

We have found that the compounds defined in the present invention, or apharmaceutically acceptable salt or in vivo hydrolysable ester thereof,are effective cell cycle inhibitors (anti-cell proliferation agents),which property is believed to arise from their CDK inhibitoryproperties. Accordingly the compounds of the present invention areexpected to be useful in the treatment of diseases or medical conditionsmediated alone or in part by CDK enzymes, i.e. the compounds may be usedto produce a CDK inhibitory effect in a warm-blooded animal in need ofsuch treatment. Thus the compounds of the present invention provide amethod for treating the proliferation of malignant cells characterisedby inhibition of CDK enzymes, i.e. the compounds may be used to producean anti-proliferative effect mediated alone or in part by the inhibitionof CDKs. Such a compound of the invention is expected to possess a widerange of anti-cancer properties as CDKs have been implicated in manycommon human cancers such as leukaemia and breast, lung, colon, rectal,stomach, prostate, bladder, pancreas and ovarian cancer. Thus it isexpected that a compound of the invention will possess anti-canceractivity against these cancers. It is in addition expected that acompound of the present invention will possess activity against a rangeof leukaemias, lymphoid malignancies and solid tumours such ascarcinomas and sarcomas in tissues such as the liver, kidney, prostateand pancreas. In particular such compounds of the invention are expectedto slow advantageously the growth of primary and recurrent solid tumoursof, for example, the colon, breast, prostate, lungs and skin. Moreparticularly such compounds of the invention, or a pharmaceuticallyacceptable salt or in vivo hydrolysable ester thereof, are expected toinhibit the growth of those primary and recurrent solid tumours whichare associated with CDKs, especially those tumours which aresignificantly dependent on CDKs for their growth and spread, includingfor example, certain tumours of the colon, breast, prostate, lung, vulvaand skin.

It is further expected that a compound of the present invention willpossess activity against other cell-proliferation diseases in a widerange of other disease states including leukaemias, fibroproliferativeand differentiative disorders, psoriasis, rheumatoid arthritis, Kaposi'ssarcoma, haemangioma, acute and chronic nephropathies, atheroma,atherosclerosis, arterial restenosis, autoimmune diseases, acute andchronic inflammation, bone diseases and ocular diseases with retinalvessel proliferation.

Thus according to this aspect of the invention there is provided acompound of the formula (I), or a pharmaceutically acceptable salt or invivo hydrolysable ester thereof, as defined hereinbefore for use as amedicament; and the use of a compound of the formula (I), or apharmaceutically acceptable salt or in vivo hydrolysable ester thereof,as defined hereinbefore in the manufacture of a medicament for use inthe production of a cell cycle inhibitory (anti-cell-proliferation)effect in a warm-blooded animal such as man. Particularly, an inhibitoryeffect is produced by preventing entry into or progression through the Sphase by inhibition of CDK2, CDK4 and/or CDK6, especially CDK2.

According to a further feature of the invention, there is provided acompound of the formula (I), or a pharmaceutically acceptable salt or invivo hydrolysable ester thereof, as defined here before in themanufacture of a medicament for use in the treatment of cancers (solidtumours and leukaemias), fibroproliferative and differentiativedisorders, psoriasis, rheumatoid arthritis, Kaposi's sarcoma,haemangioma, acute and chronic nephropathies, atheroma, atherosclerosis,arterial restenosis, autoimmune diseases, acute and chronicinflammation, bone diseases and ocular diseases with retinal vesselproliferation, particularly in the treatment of cancers.

According to a further feature of this aspect of the invention there isprovided a method for producing a cell cycle inhibitory(anti-cell-proliferation) effect in a warm-blooded animal, such as man,in need of such treatment which comprises administering to said animalan effective amount of a compound as defined immediately above.Particularly, an inhibitory effect is produced by preventing entry intoor progression through the S phase by inhibition of CDK1, CDK4 and/orCDK6, especially CDK2.

According to a further feature of this aspect of the invention there isprovided a method for producing a cell cycle inhibitory(anti-cell-proliferation) effect in a warm-blooded animal, such as man,in need of such treatment which comprises administering to said animalan effective amount of a compound as defined immediately above or apharmaceutically acceptable salt or in vivo hydrolysable ester thereof.Particularly, an inhibitory effect is produced by preventing entry intoor progression through the S phase by inhibition of CDK2, CDK4 and/orCDK6, especially CDK2.

According to an additional feature of this aspect of the invention thereis provided a method of treating cancers in a warm-blooded animal, suchas man, in need of such treatment which comprises administering to saidanimal an effective amount of a compound as defined immediately above ora pharmaceutically acceptable salt or in vivo hydrolysable esterthereof.

As stated above the size of the dose required for the therapeutic orprophylactic treatment of a particular cell-proliferation disease willnecessarily be varied depending on the host treated, the route ofadministration and the severity of the illness being treated. A unitdose in the range, for example, 1-100 mg/kg, preferably 1-50 mg/kg isenvisaged.

The CDK inhibitory activity defined hereinbefore may be applied as asole therapy or may involve, in addition to a compound of the invention,one or more other substances and/or treatments. Such conjoint treatmentmay be achieved by way of the simultaneous, sequential or separateadministration of the individual components of the treatment. In thefield of medical oncology it is normal practice to use a combination ofdifferent forms of treatment to treat each patient with cancer. Inmedical oncology the other component(s) of such conjoint treatment inaddition to the cell cycle inhibitory treatment defined hereinbefore maybe: surgery, radiotherapy or chemotherapy. Such chemotherapy may coverthree main categories of therapeutic agent:

-   (i) other cell cycle inhibitory agents that work by the same or    different mechanisms from those defined hereinbefore;-   (ii) cytostatic agents such as antioestrogens (for example    tamoxifen, toremifene, raloxifene, droloxifene, iodoxyfene),    progestogens (for example megestrol acetate), aromatase inhibitors    (for example anastrozole, letrazole, vorazole, exemestane),    antiprogestogens, antiandrogens (for example flutamide, nilutamide,    bicalutamide, cyproterone acetate), LHRH agonists and antagonists    (for example goserelin acetate, luprolide), inhibitors of    testosterone 5α-dihydroreductase (for example finasteride),    anti-invasion agents (for example metalloproteinase inhibitors like    marimastat and inhibitors of urokinase plasminogen activator    receptor function) and inhibitors of growth factor function, (such    growth factors include for example platelet derived growth factor    and hepatocyte growth factor such inhibitors include growth factor    antibodies, growth factor receptor antibodies, tyrosine kinase    inhibitors and serine/threonine kinase inhibitors); and-   (iii) antiproliferative/antineoplastic drugs and combinations    thereof, as used in medical oncology, such as antimetabolites (for    example antifolates like methotrexate, fluoropyrimidines like    5-fluorouracil, purine and adenosine analogues, cytosine    arabinoside); antitumour antibiotics (for example anthracyclines    like doxorubicin, daunomycin, epirubicin and idarubicin,    mitomycin-C, dactinomycin, mithramycin); platinum derivatives (for    example cisplatin, carboplatin); alkylating agents (for example    nitrogen mustard, melphalan, chlorambucil, busulphan,    cyclophosphamide, ifosfamide, nitrosoureas, thiotepa); antimitotic    agents (for example vinca alkaloids like vincrisitine and taxoids    like taxol, taxotere); topoisomerase inhibitors (for example    epipodophyllotoxins like etoposide and teniposide, amsacrine,    topotecan). According to this aspect of the invention there is    provided a pharmaceutical product comprising a compound of the    formula (I) as defined hereinbefore and an additional anti-tumour    substance as defined hereinbefore for the conjoint treatment of    cancer.

In addition to their use in therapeutic medicine, the compounds offormula (I) and their pharmaceutically acceptable salts are also usefulas pharmacological tools in the development and standardisation of invitro and in vivo test systems for the evaluation of the effects ofinhibitors of cell cycle activity in laboratory animals such as cats,dogs, rabbits, monkeys, rats and mice, as part of the search for newtherapeutic agents.

In the above other pharmaceutical composition, process, method, use andmedicament manufacture features, the alternative and preferredembodiments of the compounds of the invention described herein alsoapply.

EXAMPLES

The invention will now be illustrated by the following non-limitingexamples in which, unless stated otherwise:

-   (i) temperatures are given in degrees Celsius (° C.); operations    were carried out at room or ambient temperature, that is, at a    temperature in the range of 18-25° C.;-   (ii) organic solutions were dried over anhydrous magnesium sulphate;    evaporation of solvent was carried out using a rotary evaporator    under reduced pressure (600-4000 Pascals; 4.5-30 mmHg) with a bath    temperature of up to 60° C.;-   (iii) chromatography means flash chromatography on silica gel; thin    layer chromatography (TLC) was carried out on silica gel plates;-   (iv) in general, the course of reactions was followed by TLC and    reaction times are given for illustration only;-   (v) final products had satisfactory proton nuclear magnetic    resonance (NMR) spectra and/or mass spectral data;-   (vi) yields are given for illustration only and are not necessarily    those which can be obtained by diligent process development;    preparations were repeated if more material was required;-   (vii) when given, NMR data is in the form of delta values for major    diagnostic protons, given in parts per million (ppm) relative to    tetramethylsilane (TMS) as an internal standard, determined at 300    MHz using perdeuterio dimethyl sulphoxide (DMSO-d₆) as solvent    unless otherwise indicated;-   (viii) chemical symbols have their usual meanings; SI units and    symbols are used;-   (ix) solvent ratios are given in volume:volume (v/v) terms; and-   (x) mass spectra were run with an electron energy of 70 electron    volts in the chemical ionization (CI) mode using a direct exposure    probe; where indicated ionization was effected by electron impact    (EI), fast atom bombardment (FAB) or electrospray (ESP); values for    m/z are given; generally, only ions which indicate the parent mass    are reported;-   (xi) unless stated otherwise compounds containing an asymmetrically    substituted carbon and/or sulphur atom have not been resolved;-   (xii) where a synthesis is described as being analogous to that    described in a previous example the amounts used are the millimolar    ratio equivalents to those used in the previous example;-   (xvi) the following abbreviations have been used:    -   NMP 1-methyl-2-pyrrolidinone; and    -   DMSO dimethylsulphoxide.

Example 1 4-Amino-5-cyano-2-(4-sulphamoylanilino)pyrymidine

A solution of 4-amino-2-chloro-5-cyanopyrimidine (0.5 g, 3.24 mmol) and4-sulphamoylaniline (0.58 g, 3.4 mmol) in NMP (2 ml) was heated at 80°C. for 20 hours. The mixture was allowed to cool and was diluted withwater. The resulting precipitate was collected by filtration, washedwith water and dried under vacuum at 60° C. to give the title compound(889 mg, 95%). NMR: 7.08 (s, 2H), 7.60 (s, 2H), 7.67 (d, 2H), 7.95 (d,2H), 8.40 (s, 1H), 10.03 (s, 1H); m/z 291 (MH)⁺.

Example 24-Amino-5-cyano-2-{4-[N-(3-dimethylaminopropyl)sulphamoyl]anilino}pyrimidine

3-Dimethylaminopropylamine (3 ml) was added to4-amino-5-cyano-2-(4-fluorosulphonylanilino)pyrimidine (Method 1; 250mg, 0.853 mmol), the mixture was heated at 90° C. for 45 minutes thenstirred at ambient temperature for 18 hours. The volatiles were removedby evaporation and residue was purified by chromatography on silica geleluting with ethyl acetate/hexane/methanol (50:50:0) increasing inpolarity to (80:0:20). The product was triturated with ether and a fewdrops of methanol and the resulting solid collected by filtration togive the title compound (176 mg, 55%). NMR: 1.45 (t, 2H), 2.04 (s, 6H),2.10 (t, 2H), 2.72 (t, 2H), 7.60 (s, 2H), 7.62 (d, 2H), 7.98 (d, 2H),8.40 (s, 1H); m/z 376 (MH)⁺.

Examples 3-20

Following the procedure of Example 2 and using4-amino-5-cyano-2-(4-fluorosulphonylanilino)pyrimidine (Method 1) andthe appropriate amine the following compounds were prepared.

m/z Ex Compound NMR (MH)⁺  3¹ 4-Amino-5-cyano-2-{4-[N-(2- 1.30-1.48 (m,6H), 2.19-2.28 (m, 6H), 402 piperidinoethyl)sulphamoyl] 2.78 (t, 2H),7.60 (s, 2H), 7.64 (d, 2H), anilino}pyrimidine 7.98 (d, 2H), 8.40 (s,1H)  4¹ 4-Amino-5-cyano-2-(4-{N-[2- 1.18-1.30 (m, 2H), 1.45-1.80 (m,4H), 1.9- 402 (1-methylpyrrolidin-2- 2.0 (m, 2H), 2.10 (s, 3H),2.67-2.75 (m, yl)ethyl]sulphamoyl}anilino) 2H), 2.85 (m, 1H), 7.61 (s,2H), 7.64 (d, pyrimidine 2H), 8.00 (d, 2H), 8.42 (s, 1H)  5¹4-Amino-5-cyano-2-{4-[N-(2- 0.86 (d, 6H), 2.50 (m, 2H), 2.59 (m, 1H),376 isopropylaminoethyl) 2.78 (t, 2H), 7.60 (s, 2H), 7.62 (d, 2H),sulphamoyl]anilino}pyrimidine 8.00 (d, 2H), 8.40 (s, 1H), 10.25 (s, 1H) 6¹ 4-Amino-5-cyano-2-{4-[N-(3- 0.89 (d, 6H), 1.42 (m, 2H), 2.40 (t,2H), 390 isopropylaminopropyl) 2.58 (m, 1H), 2.75 (t, 2H), 7.60 (s, 2H),sulphamoyl]anilino}pyrimidine 7.62 (d, 2H), 7.98 (d, 2H), 8.40 (s, 1H) 7¹ 4-Amino-5-cyano-2-{4-[N-(2- 2.84 (t, 2H), 3.15 (s, 3H), 3.28 (t,2H), 349 methoxyethyl)sulphamoyl] 7.60 (s, 2H), 7.65 (d, 2H), 7.96 (d,2H), anilino}pyrimidine 8.40 (s, 1H)  8¹ 4-Amino-5-cyano-2-{4-[N-(3-1.56 (m, 2H), 2.73 (t, 2H), 3.12 (s, 3H), 363 methoxypropyl)sulphamoyl]3.24 (t, 2H), 7.60 (s, 2H), 7.62 (d, 2H), anilino}pyrimidine 7.98 (d,2H), 8.40 (s, 1H)  9¹ 4-Amino-5-cyano-2-{4-[N-(3- 0.99 (d, 6H), 1.53 (m,2H), 2.72 (t, 2H), 391 isopropoxypropyl)sulphamoyl] 3.28 (t, 2H), 3.40(br s, 1H), 7.35 (s, 1H), anilino}pyrimidine 7.60 (s, 2H), 7.62 (d, 2H),7.98 (d, 2H), 8.40 (s, 1H) 10¹ 4-Amino-5-cyano-2-{4-[N-(3- 1.02 (t, 3H),1.58 (q, 2H), 2.75 (t, 2H), 377 ethoxypropyl)sulphamoyl] 3.24-3.32 (m,4H), 7.38 (s, 1H), 7.60 (s, anilino}pyrimidine 2H), 7.62 (d, 2H), 7.98(d, 2H), 8.40 (s, 1H) 11¹ 4-Amino-5-cyano-2-{4-[N- 1.46-1.52 (m, 1H),1.68-1.83 (m, 3H), 375 (tetrahydrofur-2-ylmethyl) 2.72 (d, 2H), 3.55 (m,1H), 3.64 (m, 1H), sulphamoyl]anilino}pyrimidine 3.78 (m, 1H), 7.51 (s,1H), 7.60 (s, 2H), 7.64 (d, 2H), 7.98 (d, 2H), 8.40 (s, 1H) 12¹4-Amino-5-cyano-2-{4-[N-(2- 2.82 (m, 2H), 3.10 (t, 2H), 7.15-7.22 (m,394 pyrid-2-ylethyl)sulphamoyl] 3H), 7.60-7.68 (m, 4H), 7.95 (d, 2H),anilino}pyrimidine 8.39-8.42 (m, 2H) 13¹ 4-Amino-5-cyano-2-(4-{N-[3-1.46-1.58 (m, 2H), 1.8-1.9 (m, 2H), 2.15 416(2-oxopyrrolidin-1-yl)propyl] (t, 2H), 2.66 (t, 2H), 3.10 (t, 2H), 3.20(t, sulphamoyl}anilino)pyrimidine 2H), 5.98 (s, 2H), 7.61 (d, 2H), 7.98(d, 2H), 8.40 (s, 1H) 14¹ 4-Amino-5-cyano-2-{4-[N-(3- 1.50 (t, 2H),2.15-2.20 (m, 6H), 2.72 (t, 418 morpholinopropyl)sulphamoyl] 2H), 3.48(t, 4H), 7.60 (s, 2H), 7.62 (d, anilino}pyrimidine 2H), 7.98 (d, 2H),8.40 (s, 1H) 15¹ 4-Amino-5-cyano-2-{4-[N-(3- 1.7-1.8 (m, 2H), 2.62 (t,2H), 3.94 (t, 2H), 399 imidazol-1-ylpropyl) 6.85 (s, 1H), 7.08 (s, 1H),7.50 (s, 1H), sulphamoyl]anilino}pyrimidine 7.58-7.64 (m, 4H), 7.98 (d,2H), 8.40 (s, 1H) 16^(1,2) 4-Amino-5-cyano-2-[4-(N- 0.80 (t, 3H),1.11-1.2 (m, 4H), 1.35 (m, 361 pentylsulphamoyl)anilino] 2H), 2.65 (m,2H), 7.35 (t, 1H), 7.59 (s, pyrimidine 2H), 7.62 (d, 2H), 7.98 (d, 2H),8.40 (s, 1H) 17^(1,2) 4-Amino-5-cyano-2-[4-(N- 3.35 (t, 2H), 5.00 (d,1H), 5.10 (d, 1H), 331 allylsulphamoyl)anilino] 5.65 (m, 1H), 7.60 (m,3H), 7.64 (d, 2H), pyrimidine 7.98 (d, 2H), 8.40 (s, 1H) 18^(1,2)4-Amino-5-cyano-2-{4-[N-(4- 2.50-2.58 (m, 2H), 2.82 (m, 2H), 6.61 (d,411 hydroxyphenethyl)sulphamoyl] 2H), 6.90 (d, 2H), 7.48 (t, 1H), 7.60(s, anilino}pyrimidine 2H), 7.62 (d, 2H), 7.98 (d, 2H), 8.40 (s, 1H),9.12 (s, 1H) 19^(1,2) 4-Amino-5-cyano-2-{4-[N-(4- 3.92 (s, 2H), 7.08(dd, 2H), 7.24 (dd, 2H), 397 fluorobenzyl)sulphamoyl] 7.60 (s, 2H), 7.64(d, 2H), 7.98 (d, 2H), (M-H)⁻ anilino}pyrimidine 8.40 (s, 1H) 20^(1,2)4-Amino-5-cyano-2-{4-[N- 2.66 (t, 2H), 2.90 (t, 2H), 7.10-7.26 (m, 393(phenethyl)sulphamoyl] 5H), 7.58 (s, 2H), 7.62 (d, 2H), 7.98 (d, (M-H)⁻anilino}pyrimidine 2H), 8.40 (s, 1H) ¹Reaction mixture was heated at 95°C. for 2 hours ²Chromatography eluent was ethyl acetate/hexane (50:50)increasing in polarity to (100:0)

Example 214-Amino-5-cyano-2-{4-[N-(cyclobutyl)sulphamoyl]anilino}pyrimidine

Cyclobutylamine (2 ml) was added to4-amino-5-cyano-2-(4-fluorosulphonylanilino) pyrimidine (Method 1; 250mg, 0.853 mmol), the mixture was heated at 40° C. for 1 hour and thenstirred at ambient temperature for 18 hours. The volatiles were removedby evaporation and residue was purified by chromatography on silica geleluting with ethyl acetate/hexane (50:50). The product was trituratedwith ether/hexane and the resulting solid collected by filtration togive the title compound (91 mg, 31%). NMR: 1.41-1.50 (m, 2H); 1.62-1.78(m, 2H); 1.82-1.90 (m, 2H); 3.59 (m, 1H); 7.60 (s, 2H); 7.62 (d, 2H);7.98 (d, 2H); 8.40 (s, 1H); m/z: 345 (MH)⁺.

Examples 21-27

Following the procedure of Example 21 and using4-amino-5-cyano-2-(4-fluorosulphonylanilino)pyrimidine (Method 1) andthe appropriate amine the following compounds were prepared.

m/z Ex Compound NMR (MH)⁺ 22 4-Amino-5-cyano-2-{4-[N- 1.41-1.50 (m, 2H);1.62-1.78 (m, 2H); 331 (cyclopropyl)sulphamoyl]anilino} 1.82-1.90 (m,2H); 3.59 (m, 1H); 7.60 pyrimidine (s, 2H); 7.62 (d, 2H); 7.98 (d, 2H);8.40 (s, 1H) 23 4-Amino-5-cyano-2-[4-(N- 0.78 (t, 3H); 1.35 (m, 2H);2.64 (m, 333 propylsulphamoyl)anilino] 2H); 7.38 (t, 1H); 7.60 (s, 2H);7.62 (d, pyrimidine 2H); 7.98 (d, 2H); 8.40 (s, 1H) 244-Amino-5-cyano-2-{4-[N-(2,2,2- 3.62 (q, 2H); 7.60 (s, 2H); 7.70 (d,2H); 373 trifluoroethyl)sulphamoyl]anilino} 7.98 (d, 2H); 8.40 (s, 1H)pyrimidine 25 4-Amino-5-cyano-2-{4-[N-(3- 3.65 (s, 3H); 3.92 (s, 2H);6.72-6.80 (m, 409 methoxybenzyl)sulphamoyl] 3H); 7.18 (t, 1H); 7.60 (s,2H); 7.64 (d, (M-H)⁻ anilino}pyrimidine 2H); 7.98 (d, 2H); 8.40 (s, 1H)26 4-Amino-5-cyano-2-{4-[N- 0.01-0.05 (m, 2H); 0.27-0.32 (m, 2H); 345(cyclopropylmethyl)sulphamoyl] 0.69-0.79 (m, 1H); 2.58 (t, 2H); 7.50 (t,anilino}pyrimidine 1H); 7.58 (s, 2H); 7.60 (d, 2H); 7.92 (d, 2H); 8.39(s, 1H) 27 4-Amino-5-cyano-2-{4-[N-(4- 2.58 (t, 2H); 2.86 (t, 2H); 3.70(s, 3H); 423 methoxyphenethyl)sulphamoyl] 6.80 (d, 2H); 7.04 (d, 2H);7.59 (s, 2H); (M-H)⁻ anilino}pyrimidine 7.61 (d, 2H); 7.98 (d, 2H); 8.40(s, 1H)

Example 284-Amino-5-cyano-2-{4-[N-(3-imidazol-1-ylpropyl)carbamoyl]anilino}pyrimidine

A solution of 4-amino-2-chloro-5-cyanopyrimidine (200 mg, 1.3 mmol) and4-[N-(3-imidazol-1-ylpropyl)carbamoyl]aniline (Method 3; 633 mg, 2.6mmol) in NMP (10 ml) was heated at 120° C. for 48 hours. The mixture wasallowed to cool, was diluted with water and extracted with ethylacetate. The organic extracts were combined, dried and the solventremoved by evaporation, the residue was triturated with ether/hexane andthe product collected by filtration to give the title compound (10 mg,2%). NMR: 1.92 (q, 2H) 3.20 (q, 2H), 4.00 (t, 2H), 6.87 (s, 1H), 7.19(s, 1H), 7.55 (s, 2H), 7.62 (s, 1H), 7.86 (d, 2H), 8.32 (t, 1H), 8.38(s,1H), 9.90 (s, 1H); m/z 363 (MH)⁺.

Example 294-Amino-5-cyano-2-{4-[N-(2-N,N-dimethylaminoethyl)sulphamoyl]anilino}pyrimidine

2-Dimethylaminoethylamine (2 ml) was added to4-amino-5-cyano-2-(4-fluorosulphonylanilino)pyrimidine (Method 1; 250mg, 0.853 mmol) and the mixture was stirred at ambient temperature for 2hours. The volatiles were removed by evaporation and residue waspurified by chromatography eluting with ethyl acetate/hexane/methanol(50:50:0) increasing in polarity to (95:0:5). The product was trituratedwith ether and collected by filtration to give the title compound (110mg, 36%). NMR: 2.05 (s, 6H), 2.20 (t, 2H), 9.78 (t, 2H), 7.68-7.70 (m,3H), 7.98 (d, 2H), 8.40 (s, 1H); m/z 362 (MH)⁺.

Example 304-Amino-5-cyano-2-{4-[N-(3-hydroxy-2,2-dimethylpropyl)sulphamoyl]anilino}pyrimidine

A solution of 4-amino-2-chloro-5-cyanopyrimidine (150 mg, 0.97 mmol),4-[N-(3-hydroxy-2,2-dimethylpropyl)sulphamoyl]aniline (Method 4; 274 mg,1.07 mmol) in NMP (5 ml) was heated at 120° C. for 24 hours. The mixturewas allowed to cool, was diluted with water and extracted with ethylacetate. The organic extracts were combined, dried and the solventremoved by evaporation, the residue was triturated with ether and theproduct collected by filtration to give the title compound (187 mg,52%). NMR: 0.72 (s, 6H), 2.52 (d, 2H), 3.08 (d, 2H), 4.40 (t, 1H), 7.19(t, 1H), 7.60 (s, 1H), 7.64 (d, 2H), 7.96 (d, 2H), 8.40 (s, 1H); m/z 375(M−H)⁻.

Example 31 4-Amino-5-cyano-2-(3-chloroanilino)pyrimidine

3-Chloroaniline (277 mg, 2.2 mmol) was treated with4-amino-2-chloro-5-cyanopyrimidine (0.3 g, 2.0 mmol) by the proceduredescribed in Example 1 to give the title compound (430 mg, 90%). NMR:7.00 (d, 1H), 7.28 (dd, 1H), 7.55 (s, 2H), 7.70 (d, 1H), 7.89 (s, 1H),8.38 (s, 1H), 9.81 (s, 1H); m/z 246 (MH)⁺.

Preparation of Starting Materials

The starting materials for the Examples above are either commerciallyavailable or are readily prepared by standard methods from knownmaterials. For example the following reactions are illustrations but notlimitations of the preparation of some of the starting materials used inthe above reactions.

Method 1

4-Amino-5-cyano-2-(4-fluorosulphonylanilino)pyrimidine

A solution of 4-amino-2-chloro-5-cyanopyrimidine (8.0 g, 52 mmol) andsulphanilyl fluoride (9.07 g, 52 mmol) in NMP (155 ml) was heated at120° C. for 24 hours. The mixture was allowed to cool and was dilutedwith water. The resulting precipitate was collected by filtration,washed with water and dried under vacuum at 60° C. for 2 hours. Thecrude product was recrystallized from ethyl acetate/hexane to give thetitle compound (5.45 g, 37%). NMR: 7.70 (s, 24H), 7.93 (d, 2H), 8.15 (d,2H), 8.45 (s, 1H); m/z: 292 (MH)⁺.

Method 2

4-[N-(3-imidazol-1-ylpropyl)carbamoyl]nitrobenzene

A solution of 1-(3-aminopropyl)imidazole (3.87 ml, 33 mmol) in ethanol(65 ml) was added to 4-nitrobenzoyl chloride (4.0 g, 22 mmol) and themixture stirred at ambient temperature for 24 hours. The volatiles wereremoved by evaporation and the residue was dissolved in ethyl acetate,washed with water and dried. The solvent was removed by evaporation, theresidue was triturated with hexane and the product collected byfiltration to give the title compound (3.2 g, 55%). NMR: 1.98 (t, 2H),3.24 (q, 2H), 4.01 (t, 2H), 6.87 (s, 1H), 7.19 (s, 1H), 7.64 (s, 2H),8.15 (d, 2H), 8.30 (d, 2H); 8.80 (t, 1H); m/z 275 (MH)⁺.

Method 3

4-[N-(3-imidazol-1-ylpropyl)carbamoyl]aniline

10% Palladium on carbon (500 mg) was added to a solution of4-[N-(imidazol-1-ylpropyl)carbamoyl]nitrobenzene (Method 2; 3.0 g, 11mmol) dissolved in ethanol (200 ml) and ethyl acetate (50 ml). Themixture was stirred under hydrogen for 2 hours, the catalyst removed byfiltration through diatomaceous earth and the filter pad washed throughwith methanol. The solvent was removed from the filtrate by evaporationto give the title compound (1.5 g, 57%). NMR: 1.91 (t, 2H), 3.19 (q,2H), 3.98 (t, 2H), 5.58 (s, 2H), 6.52 (d, 2H), 6.86 (s, 1H), 7.19 (s,1H), 7.58 (d, 2H), 7.62 (s, 1H); 8.00 (t, 1H); m/z 245 (MH)⁺.

Method 4

4-[N-(3-hydroxy-2,2-dimethylpropyl)sulphamoyl]aniline

A mixture of sulphanilyl fluoride (1 g, 5.7 mmol),3-amino-2,2-dimethylpropan-1-ol (884 mg, 8.6 mmol) and triethylamine(0.876 ml, 6.3 mmol) in butan-1-ol (20 ml) was heated at reflux for 24hours. The volatiles were removed by evaporation and residue waspurified by chromatography on silica gel to give the title compound.NMR: 0.72 (s, 6H), 2.52 (d, 2H), 3.08 (d, 2H), 4.40 (t, 1H), 7.19 (t,1H), 7.60 (s, 1H), 7.64 (d, 2H), 7.96 (d, 2H), 8.40 (s, 1H), m/z 259(MN)⁺.

Example 32

The following illustrate representative pharmaceutical dosage formscontaining the compound of formula (I), or a pharmaceutically acceptablesalt or in vivo hydrolysable ester thereof (hereafter compound X), fortherapeutic or prophylactic use in humans:

(a): Tablet I mg/tablet Compound X 100 Lactose Ph.Eur 182.75Croscarmellose sodium 12.0 Maize starch paste (5% w/v paste) 2.25Magnesium stearate 3.0

(b): Tablet II mg/tablet Compound X 50 Lactose Ph.Eur 223.75Croscarmellose sodium 6.0 Maize starch 15.0 Polyvinylpyrrolidone (5% w/vpaste) 2.25 Magnesium stearate 3.0

(c): Tablet III mg/tablet Compound X 1.0 Lactose Ph.Eur 93.25Croscarmellose sodium 4.0 Maize starch paste (5% w/v paste) 0.75Magnesium stearate 1.0

(d): Capsule mg/capsule Compound X 10 Lactose Ph.Eur 488.5 Magnesiumstearate 1.5

(e): Injection I (50 mg/ml) Compound X 5.0% w/v

(e): Injection I (50 mg/ml) 1 M Sodium hydroxide solution 15.0% v/v 0.1M Hydrochloric acid (to adjust pH to 7.6) Polyethylene glycol 400 4.5%w/v Water for injection to 100%

(f): Injection II 10 mg/ml Compound X 1.0% w/v Sodium phosphate BP 3.6%w/v 0.1 M Sodium hydroxide solution 15.0% v/v Water for injection to100%

(g): Injection III (1 mg/ml, buffered to pH 6) Compound X  0.1% w/vSodium phosphate BP 2.26% w/v Citric acid 0.38% w/v Polyethylene glycol400  3.5% w/v Water for injection to 100%Note

The above formulations may be obtained by conventional procedures wellknown in the pharmaceutical art. The tablets (a)-(c) may be entericcoated by conventional means, for example to provide a coating ofcellulose acetate phthalate.

1. A compound of formula (I):

wherein: R¹ is halo, nitro, cyano, hydroxy, amino, carboxy, carbamoyl,mercapto, C₁₋₆alkyl, C₂₋₆alkenyl or C₂₋₆alkynyl; p is 0-4; wherein thevalues of R¹ may be the same or different; R² is sulphamoyl or a groupB-E-; wherein B is selected from C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl,C₃₋₈cycloalkyl, C₃₋₈cycloalkylC₁₋₆alkyl, phenyl, a heterocyclic group,phenylC₁₋₆alkyl or (heterocyclic group)C₁₋₆alkyl; wherein saidC₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₃₋₈cycloalkyl,C₃₋₈cycloalkylC₁₋₆alkyl, phenyl, heterocyclic group, phenylC₁₋₆alkyl or(heterocyclic group)C₁₋₆alkyl are optionally substituted on carbon byone or more D; and wherein if said heterocyclic group contains an —NH—moiety that nitrogen may be optionally substituted by a group selectedfrom G; E is —C(O)—, —N(R^(a))C(O)—, —C(O)N(R^(a))—, —S(O)_(r)—,—SO₂N(R^(a))— or —N(R^(a))SO₂—; wherein R^(a) is hydrogen or C₁₋₆alkyloptionally substituted by one or more D and r is 1-2; D is independentlyselected from halo, nitro, cyano, hydroxy, trifluoromethyl,trifluoromethoxy, amino, carboxy, carbamoyl, mercapto, sulphamoyl,C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, C₁₋₆alkanoyl,C₁₋₆alkanoyloxy, N-(C₁₋₆alkyl)amino, N,N-(C₁₋₆alkyl)₂amino,C₁₋₆alkanoylamino, N-(C₁₋₆alkyl)carbamoyl, N,N-(C₁₋₆alkyl)₂carbamoyl,C₁₋₆alkylS(O)_(a) wherein a is 0 to 2, C₁₋₆alkoxycarbonyl,N-(C₁₋₆alkyl)sulphamoyl and N,N-(C₁₋₆alkyl)₂sulphamoyl; G is selectedfrom C₁₋₄alkyl, C₁₋₄alkanoyl, C₁₋₄alkylsulphonyl, C₁₋₄alkyoxycarbonyl,carbamoyl, N-(C₁₋₄alkyl)carbamoyl, N,N-(C₁₋₄alkyl)carbamoyl, benzyl,beuzyloxycarbonyl, benzoyl and phenylsulphonyl; and q is 0-2; whereinthe values of R² maybe the same or different; and wherein p+q=1-5; withthe proviso that that compound is not2-(2,4-dimethylanilino)-4-amino-5-cyanopyrimidine; or a pharmaceuticallyacceptable salt thereof.
 2. A compound of formula (I) as claimed inclaim 1 wherein R¹ is chloro; or a pharmaceutically acceptable saltthereof.
 3. A compound of formula (I) as claimed in claim 1 wherein p is0 or 1; or a pharmaceutically acceptable salt thereof.
 4. A compound offormula (I) as claimed in claim 1 wherein R² is sulphamoyl or a groupB-E-; wherein B is selected from C₁₋₆alkyl, C₂₋₆alkenyl, C₃₋₈cycloalkyl,C₃₋₈cycloalkylC₁₋₆alkyl, phenylC₁₋₆alkyl or (heterocyclicgroup)C₁₋₆alkyl; wherein said C₁₋₆alkyl, C₂₋₆alkenyl, C₃₋₈cycloalkyl,C₃₋₈cycloalkylC₁₋₆alkyl, phenylC₁₋₆alkyl or (heterocyclicgroup)C₁₋₆alkyl are optionally substituted on carbon by one or more D;and wherein if said heterocyclic group contains an —NH— moiety thatnitrogen may be optionally substituted by a group selected from G; E is—N(R^(a))SO₂— or —N(R^(a))C(O)—; wherein R^(a) is hydrogen; D isindependently selected from halo, hydroxy, C₁₋₆alkoxy orN-(C₁₋₆alkyl)amino, N,N-(C₁₋₆alkyl)₂amino; and G is C₁₋₄alkyl; or apharmaceutically acceptable salt thereof.
 5. A compound of formula (I)as claimed in claim 1 wherein R² is selected from sulphamoyl,N-(cyclopropylmethyl)sulphamoyl, N-(tetrahydrofur-2-ylmethyl)sulphamoyl,N-(2-methoxyethyl)sulphamoyl, N-(2-pyrid-2-ylethyl)sulphamoyl,N-(2-piperidin-1-ylethyl)sulphamoyl,N-[2-(1-methylpyrrolidin-2-yl)ethyl]sulphamoyl,N-(2-isopropylaminoethyl)sulphamoyl, N-(2,2,2-trifluoroethyl)sulphamoyl,N-(2-dimethylaminoethyl)sulphamoyl, N-(3-methoxypropyl)sulphamoyl,N-(3-ethoxypropyl)sulphamoyl, N-(3-isopropoxypropyl)sulphamoyl,N-(3-dimethylaminopropyl)sulphamoyl,N-[3-(2-oxopyrrolidin-1-yl)propyl]sulphamoyl,N-(3-morpholinopropyl)sulphamoyl, N-(3-imidazol-1-ylpropyl)sulphamoyl,N-(3-isopropylaminopropyl)sulphamoyl, N-(propyl)sulphamoyl,N-(3-hydroxy-2,2-dimethylpropyl)sulphamoyl, N-(pentyl)sulphamoyl,N-(allyl)sulphamoyl, N-(cyclopropyl)sulphamoyl,N-(cyclobutyl)sulphamoyl, N-(3-methoxybenzyl)sulphamoyl,N-(4-fluorobenzyl)sulphamoyl, N-(phenethyl)sulphamoyl,N-(4-hydroxyphenethyl)sulphamoyl, N-(4-methoxyphenethyl)sulphamoyl andN-(3-imidazol-1-ylpropyl)carbamoyl; or a pharmaceutically acceptablesalt thereof.
 6. A compound of formula (I) as claimed in claim 1 whereinq is 0 or 1; or a pharmaceutically acceptable salt thereof.
 7. Acompound of formula (I) as claimed in claim 1 wherein p+q is 1; or apharmaceutically acceptable salt thereof.
 8. A compound of formula (I)as claimed in claim 1 selected from:4-amino-5-cyano-2-{4-[N-(2-methoxyethyl)sulphamoyl]anilino}pyrimidine;4-amino-5-cyano-2-{4-[N-(tetrahydrofur-2-ylmethyl)sulphamoyl]anilino}pyrimidine;4-amino-5-cyano-2-{4-[N-(4-fluorobenzyl)sulphamoyl]anilino}pyrimidine;4-amino-5-cyano-2-{4-[N-(3-methoxypropyl)sulphamoyl]anilino}pyrimidine;4-amino-5-cyano-2-{4-[N-(cyclopropyl)sulphamoyl]anilino}pyrimidine;4-amino-5-cyano-2-[4-(N-allylsulphamoyl)anilino]pyrimidine;4-amino-5-cyano-2-[4-(N-propysulphamoyl)anilino]pyrimidine;4-amino-5-cyano-2-{4-[N-(2-isopropylaminoethyl)sulphamoyl]anilino}pyrimidine;4-amino-5-cyano-2-{4-[N-(3-isopropylaminopropyl)sulphamoyl]anilino}pyrimidine;and4-amino-5-cyano-2-{4-[N-(2-piperidinoethyl)sulphamoyl]anilino}pyrimidine;or a pharmaceutically acceptable salt thereof.
 9. A process forpreparing a compound of formula (I) or a pharmaceutically acceptablesalt thereof which process (wherein R², R², p and q are, unlessotherwise specified, as defined in claim 1) comprises of: a) reaction ofa pyrimidine of formula (II):

 wherein L is a displaceable group; with an aniline of formula (III);

b) reacting a pyrimidine of formula (IV):

 wherein L is a displaceable group; with ammonia; or c) reacting acompound of formula (V):

 with a compound of formula (VI):

 wherein X is O or S; R³ is C₁₋₆alkyl; d) reacting a compound of formula(V) with a compound of formula (VII):

e) where R² is sulphamoyl or a group B-E- and E is —NHSO₂—; reacting apyrimidine of formula (VIII):

 wherein X is a displaceable group; with an amine of formula (IX):B—NH₂  (IX) and thereafter optionally: i) converting a compound of theformula (I) into another compound of the formula (I); ii) removing anyprotecting groups; iii) forming a pharmaceutically acceptable salt. 10.A pharmaceutical composition which comprises a compound of the formula(I), or a pharmaceutically acceptable salt thereof, as claimed in anyone of claims 1-8, in association with a pharmaceutically-acceptablediluent or carrier.
 11. A method for inhibiting a CDK2, CDK4 or CDK6cell cycle kinase in a warm-blooded animal in need thereof, whichcomprises administering to said animal an effective amount of a compoundof formula (I) or a pharmaceutically acceptable salt thereof as claimedin any one of claims 1-8.